The present invention relates to a valve assembly for use in a vehicle. More particularly, the present invention relates to improvements in a fuel cut off valve which can selectively cut off communication between the inside of a fuel tank and the atmosphere.
A similar fuel cut off valve is disclosed in Japanese Patent Publication No. Sho 51-21084. This publication discloses a fuel cut off valve which includes a plurality of float valves and a pair of check valves. The plurality of float valves are connected to the pair of check valves through a plurality of pipes. The plurality of float valves are located apart from each other within a fuel tank. The pair of check valves are located on an outer surface of the fuel tank. Accordingly, the inside of the fuel tank communicates with the atmosphere through the plurality of float valves, the plurality of pipes and the pair of check valves. Even when the fuel tank of a vehicle is inclined and one of the plurality of float valves is closed, the inside of the fuel tank communicates with the atmosphere through at least one of the plurality of float valves, at least one of the plurality of pipes and the pair of check valves.
Further, when the inner pressure of the fuel tank is too high one of the check valves releases the high pressure from the inside of the fuel tank. On the other hand, when the inner pressure of the fuel tank is too low another of the check valves introduces the atmosphere into the inside of the fuel tank.
The conventional fuel cut off valve does not however include a dust preventing means, thus when the one of the pair of check valves is opened to introduce the atmosphere into the fuel tank, minute dust particles and water vapor present in the atmosphere are introduced into the inside of the fuel tank.
As a result, the minute dust particles float within the fuel and water stands within the fuel tank.